• Korean Journal of Agricultural Science
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• v.38 no.4
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• pp.711-716
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• 2011

Casein micelles are the basic building block of rennet-induced gels. The stiffness of these gels is increased with reaction time. This is probably due to the continuous participation of activated casein micelles into growing network. Dual binding model of casein micelles, which explains assembly of casein and colloidal calcium phosphate, can provides fairly reasonable explanation for the changes in mechanical properties of rennet-induced gels made from different milk pHs and varying colloidal calcium phosphates. The changes in stiffness of these gels would be used for controlling textural properties of cheeses.

• Biomolecules & Therapeutics
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• v.24 no.5
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• pp.453-468
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• 2016

There is a conserved ATPase domain in topoisomerase II (topo II) and heat shock protein 90 (Hsp90) which belong to the GHKL (gyrase, Hsp90, histidine kinase, and MutL) family. The inhibitors that target each of topo II and Hsp90 are intensively studied as anti-cancer drugs since they play very important roles in cell proliferation and survival. Therefore the development of dual targeting anti-cancer drugs for topo II and Hsp90 is suggested to be a promising area. The topo II and Hsp90 inhibitors, known to bind to their ATP binding site, were searched. All the inhibitors investigated were docked to both topo II and Hsp90. Four candidate compounds as possible dual inhibitors were selected by analyzing the molecular docking study. The pharmacophore model of dual inhibitors for topo II and Hsp90 were generated and the design of novel dual inhibitor was proposed.

• Computers and Concrete
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• v.17 no.1
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• pp.53-66
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• 2016

Currently, most of the investigations on chloride diffusion were based on the experiments and simulations concerning single cation type chlorides. Chloride diffusion associated with dual or multi cation types was rarely studied. In this paper, several groups of diffusion experiments are conducted using chloride solutions containing single, dual and multi cation types. A multi-ionic model is also proposed to simulate the chloride diffusion behavior in the experimental tests. The MATLAB software is used to numerically solve the nonlinear PDEs in the multi-ionic model. The experimental and simulated results show that the chloride diffusion behavior associated with different cation types is significantly different. When the single cation type chlorides are adopted, it is found that the bound rates of chloride ions combined with divalent cations are greater than those combined with monovalent cations. When the dual/multi cation type chlorides are adopted, the chloride bound rates increase with the $Ca^{2+}/Mg^{2+}$ percentage in the source solutions. This evidence indicates that the divalent cations would markedly enhance the chloride binding capacity and reduce the chloride diffusivity. Moreover, on the basis of the analysis, it is also found that the complicated cation types in source solutions are beneficial to reducing the chloride diffusivity.

• Journal of Integrative Natural Science
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• v.5 no.1
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• pp.18-21
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• 2012

The resistance of tumour cells against cytotoxic drug is significant limitation in successful chemotherapeutic treatment of cancer. To date, no crystal structure is available for human P-gp. We developed homology model for human P-gp NBD2 by using coordinates of transporter associated protein (TAP1). Docking study was performed for 8-geranyl-chrysin (Flavonoids) inhibitor in the NBD2 model. Ligand-protein interactions were determined which indicates that the 8-geranyl chrysin shares two overlapping sites in the cytosolic domains of P-gp, the ATP site and a hydrophobic steroid-binding site.

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3219-3222
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• 2011

Three types of ${\beta}$-ketoacyl acyl carrier protein synthase (KAS) are important for overcoming the bacterial resistance problem. Recently, we reported the discovery of a antimicrobial flavonoid, YKAF01 (3,6-dihydroxyflavone), which exhibits antibacterial activity against Gram-positive bacteria through inhibition of ${\beta}$-ketoacyl acyl carrier protein synthase III (KAS III). In this report, we suggested that YKAF01 can be an inhibitor ${\beta}$-ketoacyl acyl carrier protein synthase I (KAS I) with dual inhibitory activity for KAS I as well as KAS III. KAS I is related to the elongation of unsaturated fatty acids in bacterial fatty acid synthesis and can be a good therapeutic target of designing novel antibiotics. We performed docking study of Escherichia coli KAS I (ecKAS I) and YKAF01, and determined their binding model. YKAF01 binds to KAS I with high binding affinity ($2.12{\times}10^6$) and exhibited an antimicrobial activity against the multidrug-resistant E. coli with minimal inhibitory concentration (MIC) value of 512 ${\mu}g$/mL. Further optimization of this compound will be carried out to improve its antimicrobial activity and membrane permeability against bacterial cell membrane.

• BMB Reports
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• v.48 no.10
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• pp.589-594
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• 2015

The shadow enhancer of the short gastrulation (sog) gene directs its sequential expression in the neurogenic ectoderm and the ventral midline of the developing Drosophila embryo. Here, we characterize three unusual features of the shadow enhancer midline activity. First, the minimal regions for the two different enhancer activities exhibit high overlap within the shadow enhancer, meaning that one developmental enhancer possesses dual enhancer activities. Second, the midline enhancer activity relies on five Single-minded (Sim)-binding sites, two of which have not been found in any Sim target enhancers. Finally, two linked Dorsal (Dl)- and Zelda (Zld)-binding sites, critical for the neurogenic ectoderm enhancer activity, are also required for the midline enhancer activity. These results suggest that early activation by Dl and Zld may facilitate late activation via the noncanonical sites occupied by Sim. We discuss a model for Zld as a pioneer factor and speculate its role in midline enhancer activity.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.6
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• pp.679-688
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• 2018

Autism spectrum disorders (ASDs) are neurodevelopmental disorders that share behavioral features, the results of numerous studies have suggested that the underlying causes of ASDs are multifactorial. Behavioral and/or neurobiological analyses of ASDs have been performed extensively using a valid model of prenatal exposure to valproic acid (VPA). Abnormal synapse formation resulting from altered neurite outgrowth in neural progenitor cells (NPCs) during embryonic brain development has been observed in both the VPA model and ASD subjects. Although several mechanisms have been suggested, the actual mechanism underlying enhanced neurite outgrowth remains unclear. In this study, we found that VPA enhanced the expression of brain-derived neurotrophic factor (BDNF), particularly mature BDNF (mBDNF), through dual mechanisms. VPA increased the mRNA and protein expression of BDNF by suppressing the nuclear expression of methyl-CpG-binding protein 2 (MeCP2), which is a transcriptional repressor of BDNF. In addition, VPA promoted the expression and activity of the tissue plasminogen activator (tPA), which induces BDNF maturation through proteolytic cleavage. Trichostatin A and sodium butyrate also enhanced tPA activity, but tPA activity was not induced by valpromide, which is a VPA analog that does not induce histone acetylation, indicating that histone acetylation activity was required for tPA regulation. VPA-mediated regulation of BDNF, MeCP2, and tPA was not observed in astrocytes or neurons. Therefore, these results suggested that VPA-induced mBDNF upregulation was associated with the dysregulation of MeCP2 and tPA in developing cortical NPCs.

• The Journal of Information Systems
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• v.27 no.4
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• pp.203-227
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• 2018

Purpose The purpose of this study is to investigate which decision factors continue to use the service based on the online simple payment service. In this study, we will examine how to activate the service from the continuing factors through the dual-model theory consisting of personal dedication and constraint dedication which are frequently used in relation marketing. Design/methodology/approach In this study, we investigated the activation of online simple settlement service using factors affecting the preference of the simple payment service based on the dual-model of dedication-based mechanism and constraint-based mechanism. Findings This study confirmed that customer satisfaction and convenience under the dedication -based mechanism were found to be linked to the preference of the simple payment service. Switching cost under the constraint - based mechanism showed that the customer had no binding ability to continue using the service of the current provider. Likewise, preference was found to have a direct effect on the actual frequency of use of the simple payment service, the number of uses compared to the total number of online payments, and willingness to use more.

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.11
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• pp.1358-1366
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• 1988

The dual dielectric films have been grown on single-crystalline silicon substrates with the thickness ranging from 125A to 180A at various gas and temperature conditions by using rapid thermal process that included independent nitridation step. The film characteristics and their dependence on the contents of the hydrochloric gas and the processing time have been studied. By the addition of the hydrochloric gas, the initial oxide thickness was significantly changed, but after sequential nitridation processes the thickness of the films was nevertheless a little bit varied within 10A. All the samples of the dual dielectric films show the increased breakdown voltages in proportion to the additive contents of the hydrochloric gas and also show the higher breakdown strengths than the thermal oxide and nitrided oxide films grown by the conventional furnance process or the rapid thermal nitridation process that was composed of the dependent nitridation cycles.

• Bulletin of the Korean Chemical Society
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• v.29 no.1
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• pp.111-116
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• 2008

A piperazinylalkylisoxazole library containing 86 compounds was constructed and evaluated for the binding affinities to dopamine (D3) and serotonin (5-HT2A/2C) receptor to develop antipsychotics. Dopamine antagonists (DA) showing selectivity for D3 receptor over the D2 receptor, serotonin antagonists (SA), and serotonin-dopamine dual antagonists (SDA) were identified based on their binding affinity and selectivity. The analogues were divided into three groups of 7 DAs (D3), 33 SAs (5-HT2A/2C), and 46 SDAs (D3 and 5-HT2A/2C). A classification model was generated for identifying structural characteristics of those antagonists with different affinity profiles. On the basis of the results from our previous study, we conducted the generation of the decision trees by the recursive-partitioning (RP) method using Cerius2 2D descriptors, and identified and interpreted the descriptors that discriminate in-house antipsychotic compounds.